Fact Sheet
OREXIGEN Therapeutics, Inc. is a biopharmaceutical company focused on the development of pharmaceutical product candidates for the treatment of central nervous system (CNS) disorders including obesity. We combine approved generic drugs with established safety records to create new therapeutics. Our lead product candidates reflect our understanding of how the brain appears to regulate appetite and energy expenditure, as well as the mechanisms that come into play to limit weight loss over time. These include Contrave®, which is in Phase III clinical trials, and Empatic™, which is in the later stages of Phase II clinical development.
Orexigen Highlights
- Two product candidates with blockbuster potential in underserved obesity market
- Both candidates have produced clinically significant reductions in body weight in large, randomized Phase II studies
- Both candidates mitigate safety concerns by uniquely combining drugs already approved for other indications
- Strong intellectual property position with issued U.S. composition patents on both drug candidates
- Sustained release formulations have shown meaningful improvements in tolerability, and further enhance competitive position
- Pipeline of combination products targeting other large CNS markets
Our Product Candidates
 |
Tipping the scale toward sustained weight loss: |
Contrave® is in Phase III trials for obesity. It combines bupropion SR, a well known anti-depressant, with the company’s proprietary sustained release formulation of naltrexone, a drug for alcohol and opioid addiction. While bupropion triggers an appetite suppression pathway in the brain, naltrexone keeps endorphins from slowing down appetite suppression and weight loss. Through its mechanism of action, it is believed that Contrave is the first obesity drug to address the ‘reward’ system in the brain that causes food cravings. In a Phase II study, patients who completed the trial lost between 8.0% and 10.7% in body weight over one year.
Empatic™ is in the later stages of Phase II clinical development for obesity. It combines bupropion SR with the company’s proprietary sustained release formulation of zonisamide, an anticonvulsant drug. We found that zonisamide inhibits a pathway that would otherwise counter the appetite suppression and energy expenditure induced by bupropion. This synergistic combination of drugs with a unique sustained release formulation is expected to lead to sustained weight loss and circumvent the early weight loss plateau seen with other drugs. In a Phase IIb study, patients who completed six months of treatment lost more than 10% of their body weight.
Overcoming the Weight Loss Plateau
Our lead product candidates were developed based on research on CNS mechanisms involved in the regulation of appetite and energy expenditure. Our drug combinations are designed both to generate weight loss and to limit the effect of the compensating mechanisms in the brain that prevent extended weight loss. This dual approach differentiates our drug candidates from approved weight loss drug therapies that utilize only a single active ingredient. While these monotherapeutic approaches have been shown to drive initial weight reduction, weight loss typically plateaus after several months of treatment.
In addition, we are investigating the behavioral mechanisms that drive people to eat even when not hungry. Both of Contrave’s constituents are already approved for addiction-related disorders, and we expect that together they may reduce food craving and reward.
Market Opportunity
Drugs that offer sustained weight loss with limited adverse events are critically needed to address the growing obesity epidemic and its serious impact on healthcare in the U.S. and other developed nations. There is a growing recognition within the medical community that obesity is a leading risk factor for metabolic syndrome, which comprises various co-morbidities such as diabetes, hypertension and high cholesterol.
In 2004, the Centers for Disease Control and Prevention identified obesity as the number one health threat in the United States.
- Approximately 300,000 deaths per year in the U.S. are associated with obesity according to the Department of Health and Human Services (HHS).
- In 2000, HHS estimated the overall economic costs of obesity in the U.S. to be $117 billion annually.
- Between 1980 and 2002, the rate of adult obesity in the U.S. doubled from 15% to 30%, according to the National Health and Nutrition Examination Survey. The same survey estimated that another 34% of the U.S. adult population was overweight in 2002.
Multi-layer Intellectual Property Strategy
We apply a comprehensive strategy to the protection of our intellectual property.We combine unique dosage strengths and titration regimens for Contrave and Empatic with novel, proprietary sustained release formulations that are designed to improve tolerability of the drugs. Our multiple layers of IP protection include:
- Composition of matter patents protecting the combination of specific generic drugs for therapeutic use (already issued for both Contrave and Empatic)
- Method-of-use patents protecting against combination use as treatment for obesity (Pending for Contrave, issued for Empatic.)
- Pending patents covering our proprietary sustained release formulations and titration packs further enhance our proprietary position
